3128447813 has 4 divisors (see below), whose sum is σ = 3128668620. Its totient is φ = 3128227008.

The previous prime is 3128447809. The next prime is 3128447821. The reversal of 3128447813 is 3187448213.

3128447813 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2268902689 + 859545124 = 47633^2 + 29318^2 .

It is a cyclic number.

It is not a de Polignac number, because 3128447813 - 2² = 3128447809 is a prime.

It is a super-4 number, since 4×3128447813⁴ (a number of 39 digits) contains 4444 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3128447873) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 87578 + ... + 118011.

It is an arithmetic number, because the mean of its divisors is an integer number (782167155).

Almost surely, 2^3128447813 is an apocalyptic number.

It is an amenable number.

3128447813 is a deficient number, since it is larger than the sum of its proper divisors (220807).

3128447813 is a wasteful number, since it uses less digits than its factorization.

3128447813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220806.

The product of its digits is 129024, while the sum is 41.

The square root of 3128447813 is about 55932.5291132092. The cubic root of 3128447813 is about 1462.5463496938.

It can be divided in two parts, 31284 and 47813, that added together give a palindrome (79097).

The spelling of 3128447813 in words is "three billion, one hundred twenty-eight million, four hundred forty-seven thousand, eight hundred thirteen".